Apparatus for heating fibrillary products and crimping apparatus employing same



June 4, 1968 J. VAN SILFHOUT 3,336,143

APPARATUS FOR HEATING FIBRILLARY PRODUCTS AND CRIMPING'APPARATUS EMPLOYING SAME Filed March 15. 1967 JAN WIN .S/lF/IUl/f United States Patent ABSTRACT OF THE DISCLOSURE The heating apparatus comprises a hollow chamber, which houses a cylindrically shaped or rod-like heating member. A thread reversing wheel is positioned directly over the upper end of the heating member so that the initial and final thread bearing portions of the wheel substantially overlie the thread bearing portions of the heating member. At the bottom end of the heating member, thread guides are provided. The thread to be heated enters an eyelet at the bottom of the chamber, passes over one of the guides and upward and helically around the heating element, over the reversing Wheel and helically down another portion of the heating element, over the other thread guide, through a second outlet and directly into the nip of a pair of rolls feeding to a stutter box crimper. The reversing wheel can be displaced to a position beside and at the bottom of the heating member to facilitate system thread-in.

This invention relates to an apparatus for heating a continuously moving fibrillary or thread-shaped product having a heating means uniquely arranged to provide a long heating Zone in a small space. This invention also relates to a crimping apparatus of the box or chambertype provided with such heating apparatus.

In the textile industry the heating of continuously moving thread-shaped products is used in many diverse processes. Examples of such processes are drying, drawing, shrinkproofing, plasticizing for false twisting and plasticizing for box-crimping. Although the heating apparatus of this invention will hereinafter be described with reference to its use with an apparatus used in the boxcrimping process, it will be recognized that the heating apparatus according to the invention can be used in a similar way and with equal success in other yarn treatments.

It has been found that the box-crimping of synthetic thermoplastic yarns, threads, and the like fibrillary products runs more smoothly and can be controlled better if the yarn is heated before it is fed into the crimping box or chamber. However, the yarn must be heated thoroughly before entering the crimping box.

In the box-crimping process, long heating zones are required, particularly when the yarn speed is raised to 1000 meters per minute or higher. These long heating zones, which may be aslong as 2 to 4 meters, considerably complicate the designing of a box-crimping apparatus.

It should be noted that with the known box-crimping apparatus which operate at very much lower yarn speeds, heating of the yarn is hardly any problem. The required length of the heating zone in the known apparatus is so short that in all the process steps the yarn may travel along a substantially straight path. Hence, a mu'lti-position machine used for this type of crimping may be of compact construction, because at each position all the yarn treatments can be carried out in a narrow and fairly 3,386,143 Patented June 4, 196.8

short zone. If the heating zones are as long as 2 to 4 meters, however, the conventional designs are no longer suitable to be used for constructing a compact box-crimping apparatus.

It has already been proposed to accommodate an apparatus on more than one floor. The feed section of such an apparatus is mounted, for example, on a higher floor than the crimping section and the winding system. It will be clear that such a construction is very costly.

Advantageously, the present invention provides an apparatus for heating yarns, threads and the like fibrillary products which combines a long heating zone with a very compact construction.

Thus this invention contemplates an apparatus for heating a continuously moving thread or the like fibrillary product which comprises a substantially vertical cylindrically-shaped heating member, two thread guides mounted diametrically opposite each other on the heating member near its bottom end, thread-reversing means in its operating position facing the top end of the heating member for guiding a thread from one of said thread guides upwardly along one portion of the heating member and downwardly along another portion of the heating member to the other thread guide, and guide means for allowing said thread-reversing means to be swung away from said operating position to an upper position beside the top end of said heating member and for thereafter positioning said thread-reversing means in a lower position adjacent to the bottom end of the heating member whereby said thread is heated by said heating member in the operating position of said thread-reversing means and is easily threaded-in at the lower position of said threadreversing means.

As herein dmcribed in greater detail, the guide means of the apparatus includes a guide member which extends vertically alongside of the heating member and a support for the thread-reversing means which is coupled to the guide member so that thread-reversing means can swing towards and away from its operating position over the top of the heating member and the support can slide upwardly and downwardly alongside of the heating member.

In accordance with this invention, the apparatus is operated as follows: For the purpose of threading-in, the thread-reversing means is moved downwards alongside of the heating member. Subsequently, a thread or like fibrillary product is first passed over one thread guide, then over the thread-reversing means, and finally over the second thread guide. The thread-reversing means is then moved upwards alongside of the heating member and finally swung inwardly into its operating position in which it faces the top end of the heating member. As a result of the swinging movement of the thread-reversing means the thread will come into contact with the heating member along helically-shaped paths, one running in an upward direction and the other in a downward direction. In this way, the length of said heating member is twice used to provide a relatively long heating zone for the thread.

Since the thread lies on the heating member in a very long loop, the engaging end of the thread and the disengaging end thereof are close together. As a result, the thread-feeding system, the thread withdrawing rollers, and the Winding system of the apparatus are mounted close together and are constructed as a compact unit. Moreover, threading-in of the heating apparatus is simple and can be done within a very limited space.

It should be noted that various other constructions are possible in which the thread end engaging the heating member and the end disengaging from the member are positioned close together. Examples of such constructions are a rotating roller, two adjacent curved plates,

and a curved tubular oven. It has been found that all these apparatus either lead to costly constructions or have other disadvantages. These disadvantages are usually of a constructional or operational nature. As far as the operational disadvantages are concerned, many of the abovementioned types of possible apparatus present great dithculties with regard to threading-in or are difficult to clean in the case of thread breakage.

Although it is possible to slide the thread-reversing means upwards and downwards along the guide manually or by a mechanical means, it has been found that an embodiment according to the invention is preferred. This embodiment is characterized in that the threadreversing means is kept in its operating position by a load biasing means such as a spring or a weight. After threading-in, the thread-reversing means may simply be released whereupon under theinfiuence of the biasing means, it is automatically moved upwardly and maintained above the heating member so that it can be readily swung into its operating position.

In order to move the thread-reversing means into the position in which threading-in may take place, it is according to the invention preferred to use as a guide member a tubular member and to provide therein a pneumatic system for moving, against the biasing action of the spring or weight, the thread-reversing means in a downward direction.

Known cylindrically-shaped heating members are as a rule heated electrically. For example, the heating member may comprise a hollow cylinder containing an electric resistor. Also, the cylinder itself may be made of electrically resistant material and connected to a source of electric current. Either construction could be used in the apparatus according to the invention. It has been found, however, that it is difficult to uniformly heat a relatively long heating member by electrical means. It is therefore preferred to use an embodiment of the heating member according to the invention in which the cylindrically-shaped heating member is a tubular member which is connected to a steam feed line and a steam discharge line. It has been found that in this way a very simple construction may be obtained, and that by using such an arrangement, a very uniform temperature is ob tained throughout the heating member.

In addition to the above-described heating apparatus, the invention also concerns a crimping apparatus of the boxor chamber-type provided with such a heating apparatus. Although the heating apparatus may take up a number of positions relative to the feed rollers used in the crimping apparatus, it is according to the invention preferred to use a construction in which the heating apparatus is positioned before and at a short distance from the feed rollers in such a manner that the generatrix of the heating member (i.e., the line which generates its heating surface) which passes through the thread guide adjacent to the disengaging end of the thread substantially coincides with the extended longitudinal axis of the stuffer box or crimping chamber. In this way, the thread, during and after heating and before it is passed between the feed rollers, is given the smallest possible number of wraps around the heating member. As a result, the tension in the thread passed between the feed rollers can be kept very uniform.

For the purposes of understanding the invention, reference is made to the accompanying drawings in which:

FIGURE 1 schematically shows a box-crimping apparatus employing the heating apparatus of the invention;

FIGURE 2 shows in side elevation the heating apparatus of the invention with its door open;

FIGURE 3 shows the heating apparatus in section taken along line IIIIII in FIGURE 2; and

FIGURE 4 shows the heating apparatus with its door closed with its heating member in the position used for heating fibrillary products as shown in FIGURE 1.

In FIGURE 1, the reference numeral 1 refers to a thread passing through the heating apparatus which is subsequently passed through the schematically represented stuifer box or crimping chamber 2 and then wound into a yarn package 3. The heating apparatus comprises a hollow chamber 4, which houses a cylindrically-shaped or rod-like heating member 5. A thread-reversing wheel '6 faces the top end of the heating member, i.e., the wheel is positioned directly over the upper end or surface of the member 5 so that (as shown in FIGUREA) the initial and final thread-bearing portions of the wheel substantially overlie the thread-bearing portions of the heating member. At the bottom end of the heating member two pinthread guides are provided on diametrically opposite sides and near two eyelets or openings 9 and 10 in the bottom of the chamber 4.

During the heating operation of the apparatus, thread 1 passes from a feed system (not shown) through the eyelet 9, around the back of the pin 7, in an upwar direction in a very steep helical path to the thread-reversing wheel 6. After passing over the wheel, the thread travels along the heating member 5 in a similar steep helical path in a downward direction. At the bottom end of the heating member, the thread 1 passes in front of the pin 8 and is subsequently guided through the eyelet It) to a pair of thread withdrawing rollers which also serve as feed rollers for the stuft'er box 2. The rod-shaped heating member is preferably 2 meters in length, which provides an effective length for its heating surface of 4 mete-rs.

As shown in FIGURE 2, the thread-reversing wheel 6 is swung outwards away from the heating member and in its upper position. FIGURE 3 shows a portion of the apparatus in a plan view and in section taken along line IIIIII on FIGURE 2. In FIGURE 2 as well as in FIG- URE 3, the thread-reversing wheel is swung outwardly away from the top of the heating member.

As shown in FIGURE 3, a door 11 is attached to the chamber 4 by a hinge 12. The thread-reversing wheel 6 is coupled to a guide sleeve 13 by means of a support shaft 14 on which the thread-reversing wheel 6 is rotatable. The guide sleeve 13 may he slid up and down on a guide tube 15. At its top end and its bottom end the guide tube is attached to the door 11 by supports 16 and 17. The support 17 is constructed to also provide a tubular inlet through which compressed air may be fed to the bottom end of the guide tube 15.

Provided over the top end of the tube 15 is a pulley 18. A rope 19 is passed over this pulley. One end of the rope is attached to the shaft 14 on which the threadreversing wheel 6 rotates and the other end is secured to a piston 20 which fits in the guide tube 15. The weight of the piston 20 is greater than that of the thread-reversing wheel 6, the shaft 14, and the guide sleeve 13 together. As a result, the weight of the piston 20 will, by means of the rope 19, pull the thread-reversing wheel 6 in an upward direction. The piston 20 is shown positioned in the guide tube 15 by a partial section in FIGURE 2.

FIGURE 4 shows the position of the thread-reversing wheel 6 relative to the heating member when the door 11 is closed and when the thread is placed in contact with the heating member 5. It will be seen that the wheel is positioned directly over the end of the heating member so that the thread reverses its direction of travel to form steeply inclined helices along substantial portions of the cylindrical surface of the heating member.

Provided at the bottom end of the heating member are two tubular conduits 21 and 22 for supplying and discharging steam, respectively.

The threading-in of thread through the heating apparatus is carried out as follows. First, the thread 1 is passed through the eyelet 9, around the back of the pin 7, over the lower front portion of the heating member 5, in front of the pin 8 and through the eyelet 10. Of course,

this is done with the door 11 open, as shown in FIG- URE 3. Subsequently, compressed air is fed through the tubular support member 17. As a result, the piston 20 is caused to move upwardly. Since, when the door 11 is open, the thread-reversing wheel is positioned beside the heating member rather than directly over it, an upward movement of the piston 20 will cause the thread-reversing wheel together with the guide sleeve to move downwardly alongside the guide tube 15. When the threadreversing wheel is in its lowest position, the thread loop between the pin 7 and the pin 8 is passed over the wheel 6 and placed on its grooved thread-bearing surface. The air pressure under the piston 20 is then removed. As a result, the piston 20 moves downwardly under its own weight and gradually pulls the thread-reversing wheel in an upward direction to the upper position shown in FIG- URE 2.

When the door 11 is then closed, the thread-reversing wheel is, as can be seen from FIGURE 4, swung into its operating position in which it faces the top end of the heating member 5 and the two parts of the thread loop between the thread-reversing wheel 6 and the pins 7 and 8 will be in substantial contact with the heating member 5 along two steep helical paths.

While the novel features of the invention have been shown and described and are pointed out in the appended claims, it is to be understood that various omissions, substitutions and changes in construction and arrangement of the features shown and described may be made by those skilled in the art without departing from the spirit and scope of the invention.

What is claimed is:

1. An apparatus for heating a continuously moving thread or the like fibrillary product which comprises a substantially vertical cylindrically-shaped heating member, two thread guides mounted diametrically opposite each other on the heating member near its bottom end, thread-reversing means in its operating position facing the top end of the heating member for guiding a thread from one of said thread guides upwardly along one portion of the heating member and downwardly along another portion of the heating member to the other thread guide, and guide means for allowing said thread-reversing means to be swung away from said operating position to an upper position beside the top end of said heating member and for thereafter positioning said thread-reversing means in a lower position adjacent to the bottom end of the heating member whereby said thread is heated by said heating member in the operating position of said thread-reversing means and is easily threaded-in at the lower position of said thread-reversing means.

2. The heating apparatus of claim 1 in which said guide means includes a guide member which extends vertically alongside of said heating member and a support for said thread-reversing means, said support being operatively associated with said guide member to swing said thread-reversing means from its operating position to said upper position and thereafter to slide alongside of said heating member to position said thread-reversing means in its lower position.

3. The heating apparatus of claim 2 in which said guide means is provided with a load biasing means operatively associated with said guide member and said support for maintaining said thread-reversing means in its operating position.

4. The heating apparatus of claim 3 in which said guide member is a tubular member having a pneumatic system therein for moving said thread-reversing means in a downward direction against the biasing action of said load-biasing means.

5. The heating apparatus of claim 1 in which said heating member is a tubular member which is connected to a steam feed line and a steam discharge line.

6. An apparatus for crimping thread and the like fibrillary products which comprises means for heating a continuously moving thread, said means comprising a substantially vertical cylindrically-shaped heating member, two thread guides mounted diametrically opposite each other on the heating member near its bottom end, and thread-reversing means facing the top end of the heating member for guiding said thread from one of said thread guides upwardly along one portion of the heating member and downwardly along another portion of the heating member to the other th ead guide, a pair of feed rollers for withdrawing the thread from said other thread guide and for feeding the thread to a stutter box, said rollers being positioned to feed said thread substantially along the longitudinal axis of said stufler box and said heating means being positioned before and at a short distance from said feed rollers so that the generatrix of said cylindrically-shaped heating member which passes through said other thread guide substantially coincides with the extended longitudinal axis of said stutter box.

References Cited UNITED STATES PATENTS 3,067,563 12/1962 Van Dijk 5734 3,321,904 5/1967 Horvath et al. 28-62 FOREIGN PATENTS 99,482 10/ 1961 Netherlands. 121,160 9/ 1958 U.S.S.R. 1,154,262 10/1957 France.

ROBERT R. MACKEY, Acting Primary Examiner.

IRA C. WADDEY, Assistant Examiner. 

